Method for dielectrically heat sealing the end cover of a headrest and forming a peripheral welt therearound



Oct. 21, 1969 D A. GOLD 3,473,208

METHOD FOR DIELECTRICALUL' HEAT SEALING 'JHE END COVER OF A HEADREST ANDFORMING A PERIPHERAL WELT THEREAROUND Filed May 29, 1967 United StatesPatent US. Cl. 29-911 Claims ABSTRACT OF THE DISCLOSURE A headrestforming method including the steps of inserting an open-ended coversleeve that incases an interior cushion into a close fitting hollowshell and turning an end portion thereof out over the edge of the shellto form a turnback and back along the exterior of the shell. Thenstretching a sized endless elastic band over the turned back portion andfolding the turned back portion forwardly over the band and inwardlyover the end of the shell. Thereafter, placing the cover over theinwardly turned portion and sealing it thereto and also sealing theinwardly turned portion to the turnback to seal the band in the endportion to define the welt. Then upturning the welt by rolling it offthe end of the shell.

BACKGROUND OF INVENTION Field of invention The present invention relatesgenerally to heat sealed cushions and more particularly to a method forattaching a headrest end cover and for forming a peripheral welttherearound.

Description of prior art Presently existing headrests such as that shownand described in Patent No. 3,245,719, issued Apr. 12, 1966, aregenerally made without peripheral end welts and those which are madewith such welts are relatively expensive to manufacture. Since theinterior cushion must be installed in the cover sleeve before theclosing end cover is attached it is diflicult to form a peripheral weltin the closing end cover attaching seam.

SUMMARY OF INVENTION Accordingly it is an object of the presentinvention to provide a convenient method for attaching the closing endcover of a headrest and forming a peripheral welt therearound.

It is a further object of the invention to provide a method of the typedescribed that employs heat to form the seal between the cover andsleeve.

It is another object of the invention to provide a method of the typedescribed wherein the end cover is presized such that its peripheraledge is concealed beneath the welt in the finished headrest.

It is a more particular object of the invention to provide a methodcomprised of the steps of inserting a cushioncontaining open-ended coversleeve into a close fitting open-ended hollow shell and turning aportion of the sleeve adjacent the open end out over the edge of theshell to form a turnback and back along the exterior of the shell toform a return. Then stretching a sized endless elastic band over thereturn and folding said return forwardly over the exterior of the bandand inwardly to form a border overlying the turnback. The cover is thenplaced over the open end of the sleeve with its periphery overlying theborder and is sealed thereto. The border is also sealed to the turnbackthus sealing the band in the turnback to form the welt. The finishedheadrest is then 3,473,208 Patented Oct. 21, 1969 removed from the shellby upturning the welt and sliding it therefrom.

Other objects and features of the invention will become apparent fromconsideration of the following description taken in conjunction with theaccompanying drawmgs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of ashell employed in a preferred method embodying the present invention;

FIG. 2 is a horizontal sectional view taken along the lines 2-2 of FIG.1 and showing the shell fitted around a headrest;

FIG. 3 is an elevation view, in smaller scale, of the shell shown inFIG. 1, a headrest being shown extending therefrom;

FIG. 4 is a partial elevational sectional view, in enlarged scale, takenalong the lines 4-4 of FIG. 3;

FIG. 5 is a partial vertical sectional view, in enlarged scale, takenalong the lines 4-4 of FIG. 3, the elastic band being shown in position;

FIG. 6 is a partial vertical sectional view, in enlarged scale, takenalong the lines 4-4 of FIG. 3, the cover being shown in place;

FIG. 7 is a partial vertical sectional view taken along the lines 77 ofFIG. 5;

FIG. 8 is a reduced perspective view of a headrest manufactured by amethod embodying the present invention; and

FIG. 9 is a partial vertical sectional view, in enlarged scale, takenalong the lines 9-9 of FIG. 8.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, FIG.8 shows a completed headrest H, manufactured by the method of presentinvention. The headrest H generally includes an elongated cylindricalfoam rubber cushion 11 that is covered by an open-ended cover sleeve,generally designated 13, and a pair of like end covers, one of which isshown at 15; the headrest being mountable by a mount 16. In making theheadrest H one of the end covers 15 is attached to one end of the sleeve13, the cushion 11 forced into the sleeve and an open-endedlongitudinally-hinged shell 17 buckled over the sleeve 13. The portion,generally designated 19, adjacent the open end of the sleeve is turnedoutwardly and back on the shell 17 and an elastic band 21, as shown inFIG. 5, is fitted thereover. The end portion 19 is then folded back overthe elastic band 21 to define a welt, generally designated 23, andinwardly over the top edge of the shell 17. The cover 15 is placed overthe inwardly folded sleeve and sealed thereto and at the same time theoverlying layers of sleeve are sealed together to seal the elastic band21 in place.

More particularly, the preliminary steps of constructing the headrest Hare similar to those described in the earlier patent, 3,245,719,including forming the cylindrical cover sleeve 13 by heat-sealingopposite longitudinal ends of a rectangular sheet of heat scalableplastic together.

The mount 16 includes an elongated bar 29 having a pair of right anglebrackets 31 attached near opposite ends thereof and is inserted in thesleeve 13 and the ends of the brackets 31 extended outwardly throughspaced holes in the sleeve. One end of the sleeve 13 is then covered byan end cover 15 of heat-scalable plastic and a welt 35 formed by thesealing joint. Since the cushion 11 has not yet been installed thesleeve 13 can be turned inside out at this time and the welt 35 formingseal made in a conventional manner, or, if desired, in the same manneras described below for forming the welt 23.

The cushion 11 includes a longitudinal slit 37 that extends radiallyinto the center from one periphery for receiving the mount bar 29. Thecushion is inserted in through the open end 39 of the sleeve 13 bycompressing the cushion radially inwardly and sliding the sleeves 13thereover. Since the cushion 11 is readily compressible the bar 29 canbe properly positioned in the slot 37 after the sleeve 13 has beenfitted thereover.

The shell 17 comprises two semicylindrical halves 41 that are hingedtogether on one side by a longitudinal piano-type hinge 42. The freesides of the halves are fastenable together by conventional buckles 43and include confronting recesses 44 that cooperate to receive thebrackets 31 when the shell 17 is closed. A bandreceiving groove 45 ismachined near the upper end of the shell 17 and an access groove 47 ismachined immediately therebeside. A plurality of radial grooves 49 arecut across the edge 51 of the shell 17 to provide more effectiveheat-sealing, as shown in FIG. 7. The open shell 17 is placed around thecushion-containing sleeve 13 and buckled with the sleeve end portion 19and cushion 13 extending therefrom. The sleeve end portion 19 is thenfolded out over the shell edge 51 to form a turnback 53 and back alongthe exterior of the shell to form a return 55 that overlies the grooves45 and 47 as shown in FIG. 4.

The band 21 is then stretched over the return 55 pressing the underlyingportion into the groove 45 as shown in FIG. 5. The free end of thereturn is then grasped by inserting the tips of the finger into theaccess groove 47 and is folded back over the band 21 and inwardly overthe shell edge 51 to form an annular border 59 overlying the turnback 53as shown in FIG. 6. The presized circular end cover is then placed overthe end of the sleeve 13 with its peripheral portion overlying theannular border 59 as shown in FIG. 6. The central portion of the cover15 is pressed downwardly to longitudinally compress the cushion 13 evenwith the end of the shell 17 and its annular peripheral area is pressedagainst the shell edge 51 by a heat-sealing ring 61 having an annularabutting surface that complements the annular edge 51. Electric currentis then passed through the plate 61 and shell 17 causing the pressedannular area of the cover 15, border 59 and turnback 53 to act as adielectric, thus heating the edge 51 and causing the adjacent plasticsto be heat-sealed together. This provides a circular heat seal betweenthe cover 15, border 59 and turnback 53 thus sealing the cover to theend of the sleeve 13 and sealing the band 21 within the return 55 todefine the Welt 23, as shown in FIG. 6. The plate 61 is then removed andthe welt 23 upturned by rolling it out of the groove 45. Finally, theshell 17 is unbuckled and the finished headrest H removed therefrom.

The cushion 13 will then expand axially against the end cover 15 toforce its central portion axially outwardly thus forcing the portion 63adjacent the welt 23 to assume a contour abutting the radial inner sideof the welt 23 to conceal the peripheral edge 65 of the end cover, asshown in FIG. 9. By utilizing the presized cover 15, the necessity offinish trimming is avoided because in the finished joint or seal theperipheral portion 65 of the end cover 15 will be concealed beneath theWelt 23.

From the foregoing it will be seen that the method of this inventionprovides an easy and inexpensive means for attaching the closing endcover 15 of a headrest H and forming a welt 23 to give the headrest anaesthetic appearance.

Various modifications and changes may be made with regard to theforegoing detailed description without departing from the spirit of theinvention or the scope of the following claims.

I claim:

1. The steps in a method for attaching the end cover of a headrest andforming a peripheral welt therearound, said headrest being of the typethat includes an openended sleeve encasing an interior cushion, a sizedendless elastic band and an end cover, said steps comprising:

inserting said open-ended sleeve into a close fitting open-ended hollowshell and turning an end portion thereof out over the edge of said openend of said shell to form a turnback and back along the outer surface ofsaid shell to form a return;

stretching said elastic band around said shell and over said return;

folding said return back over the outer surface of said band andinwardly over said edge of said shell to form a border overlying saidturnback;

placing said cover over said open end of said shell with its peripheryoverlying said border and sealing said cover to said border and saidborder to said turnback thereby sealing said band in said turnback todefine said welt; and

upturning said welt by thereafter rolling it ofl? Said open end of saidshell and removing said headrest fromsaid shell.

2. A method as set forth in claim 1 wherein said cover, border andturnback are heat sealed together.

3. A method as set forth in claim 1 wherein said shell is ofelectrically conductive material and said sealing step includes placingan electrically conductive plate over said end of said shell overlyingsaid cover and conducting electrical current therethrough and throughsaid cover, border, turnback and shell.

4. A method as set forth in claim 1 that includes a step before saidstep of sealing said cover to said border of cutting said cover to asize such that its peripheral edge is concealed by said welt when saidwelt is upturned.

5. A method as set forth in claim 1 wherein said headrest is of the typethat includes an elongated internal cushion in said sleeve and saidmethod includes a step for compressing said cushion longitudinally intosaid sleeve and maintaining it compressed while said cover is sealed,thereby causing said cover of the finished headrest to be pressed firmlyoutwardly by said cushion.

References Cited UNITED STATES PATENTS 3,245,719 4/ 1966 Davidson297-397 3,346,934 10/1967 Davidson 299l.l

THOMAS H. EAGER, Primary Examiner

